PROJECT SUMMARY/ABSTRACT The UC Davis Comprehensive Cancer Center (CCC) Mouse Biology (MB) Shared Resource (SR) is one of the original cores initially established by the first CCSG submission. At the last competitive renewal, the MB SR received a rating score of outstanding to exceptional and several laudable comments from CCSG reviewers. Building upon that earlier success, and recognizing the essential importance of indicant mutations in the mouse genome to advances in research on the biology, diagnosis, treatment, and prevention of cancer in humans, the MB SR continues to be a critically integral component of the research mission of the CCC. Utilizing the wide breadth and depth of expertise and infrastructure of the UC Davis Mouse Biology Program, the MB SR serves and supports cancer-related research by CCC members utilizing genetically-altered mice. The MB SR provides all of the necessary technical elements for de novo creation and derivation of transgenic, knockout, and other types of induced mutant mice, husbandry, maintenance, health-care, and well-being of mice, and an extensive array of genotyping and phenotyping capabilities and services to CCC members on a prioritized basis and at a subsidized cost. In addition, MB SR leadership faculty and their associates contribute intellectually to the development of research areas and projects by CCC members who incorporate mouse models into their research. Since its inception, the success of the MB SR to the overall mission of the CCC is immediately evident by noting the accomplishments of the 25 CCC members requesting more than 26,309 services in support of their cancer-related research in just the last year of the CCSG. In this competitive renewal, the MB SR intends to continue to offer superior technical excellence and scientific input in anticipation of an increasing number of requests from CCC members during the next 5 years. The specific aims of the MB SR are divided into 3 principal service categories: 1) Mouse Modeling and Creation Services; 2) Mouse Husbandry and Maintenance Services; and 3) Mouse Genotyping and Phenotyping Services.